Miniature rocket nozzle



April 8, 1969 1', 'BlEHL ET 'AL 3,437,289

7 MINIATURE aocxm NOZZLE Original Filed April 4, 1966 KIKKK'"? I. 4

ARTHUR T. BIEHL .ROBERTMAHARDT US. Cl. 244--3.23 2 Claims ABSTRACT OFTHE DISCLOSURE The invention relates to miniature rockets provided withpropellant means arranged to be ignited by a primer cap positionedwithin a cavity of an integrated preformed nozzle provided withequidistantly disposed ruptured gas venting means. It is alsocontemplated to have a protected blow-out disc interposed between thepropellant and the preformed nozzle.

This application is a divisional application of our copendingapplication Ser. No. 541,919, filed April 4, 1966, now Patent No.3,345,902, which was a continuation-inpart application of Ser. No.210,270, filed July 16, 196-2, the latter application being nowabandoned.

This invention relates to an improved article of manufacture and itsmethod of making. More particularly, the inventive concept relates to aminiature rocket as well as the new nozzle elements from which it isconstructed.

The miniature ballistic rockets that have been revealed by theapplicants are unusually etfective in ordnance applications. The sizerange which is appropriate for the indicated miniature rocketscorresponds to the size range of conventional side arm rifle andpossibly higher gauge shotgun calibers. In order to maintain theminiature size of these rockets, as well as allowing their use inconventional weapons with the attendant advantages, it is vitallyimportant to provide a novel structure which will make the rockets moreaerodynamically stable, thus eliminating the need for fins. As thelaunch tube diameter in most applications governs the dimension of arocket, the removal of fins therefrom will allow a more productiveutilization of this available diameter. Finless projectiles have manydistinct advantages over conventional finned rockets, such as, betterpacking densities, easy to manufacture, easy to adapt to conventionalweapons and more productively utilize the available volume than finnedprojectiles.

The use of a nozzle structure which converts linear momentum intoangular momentum thereby bringing about rotation of the rocket in flightmay be incorporated into miniature ballistic rockets while maintaining astructure which is easy to manufacture.

Simplicity of rocket design is of primary importance if the number ofrockets produced is to be comparable with conventional bullets.Commensurate with this goal is the provision of a nozzle design whichincorporates a primer cap or other ignition means in its structure whilestill maintaining its simplicity which will even further decrease themanufacturing expense and increase the usefulness of every round. Thus,it will be apparent that one of the most important factors in rocketryand particularly in the nozzle designs, is that they must be easilyassemblable into the casing, particularly when the small size isconsidered.

Accordingly, nozzle designs may be also made which incorporate means forproviding a restraining force on the rocket until the desired thrustmagnitude is reached. This restraint prevents the premature launching ofthe rocket and erratic initial aerodynamic performance and nited StatesPatent thus allows a controlled set of launching conditions for everyrocket.

One of the objects of the invention is to provide for the manufactureand assembly of a new type of rocket.

Another object of this invention is to provide a nozzle structure whichmay be utilized with conventional firearms.

Still another object of this invention is to provide a nozzle structurefor a miniature ballistic rocket in which an ignition means isincorporated.

Yet another object of this invention is to provide a sealing means whichis positioned over the primer chamber and the surrounding nozzles beforethe rocket is assembled.

Other objects and advantages will become apparent upon consideration ofthe following specification taken with the accompanying drawings whichtogether form a complete disclosure of the invention, in which:

FIG. 1 shows a view in cross-section of the die members of oneembodiment of the invention preparatory to upsetting a disc of metal toform the nozzle;

FIG. 2 is still another cross-sectional view of the die members afterthey have been brought into contacting relation with the disc anddeformed it as shown:

FIG. 3 is a view generally similar to FIG. 2 which shows a prickingdevice for longitudinally aperturing the projecting chamber;

FIG. 4 is an end elevational view of the complete nozzle subsequent toits deformation;

FIG. 5 is a cross-sectional view of a propellant preparatory to beinginserted in a cartridge casing;

FIG. 6 is a view partially in cross-section and partially in elevationshowing the nozzle being introduced into the rocket casing;

FIG. 7 is a view of the completed rocket assembly shown partially incross-section and partially in elevation; and

FIG. 8 is an end elevational view of the completed nozzle of anotherembodiment of the invention, the exhaust vents of which are created by adifferent type of die forming means.

Turning now to the drawings, and more particularly the view of FIG. 1,there is illustrated in cross-section a pair of die forming memberscomprising a male member 10 and a female member 12, the latter memberbeing provided with any suitable means, such as shown at 14, to supportthe disc member 16, which is shown in elevation.

The axial center portion of the male member 10 is provided with acylindrical portion 18 which terminates forwardly thereof in a chamferedportion 20 so that when the enlarged portion 18 is forced or punchedinto the disc under suitable pressure by means not shown, the disc isupset in the center area into the complementally formed recess 22provided in the female die member.

Although there is provided, as shown in FIG. 1, an axially extendingperforation 24 in the male member 10 which is adapted to accommodate areciprocable pricking punch means 26 for penetrating the upset center ofthe disc after it has been upset, it is also contemplated that thispricking operation can be achieved simultaneously rather thansequentially.

With further reference to the drawings, and particularly FIG. 2, it isto be understood that the male die member 10 includes a plurality ofsubstantially equidistantly disposed coextensive angularly arrangeddeforming means 28-28 (only two shown) which, when the upsettingoperation takes place, distort the wall of the disc in predeterminedareas, as indicated at 30-30, to Such an extent that they ultimatelyfracture tangentially thereof. This is best shown in FIG. 4.

FIG. 3 clearly shows the disc 16 under full or maximum pressure of thedie members 10 and 12 at about the time of the fracturing of the walls3030 thereof. Substantially simultaneously with the application ofmaximum pressure to distort the disc to deform the metallic wallstructure thereby forming the chamber 31, or immediately thereafter, thereciprocable pricking means 26 is advanced through the perforation 24provided in the male member thence through the aperture 32 in the femalemember to thus form the completed nozzle 34.

Prior to describing the final steps in the assembly operation and atwhich time the rocket is formed, the die formation of a furtherembodiment of another and different type of nozzle will be discussed.

Reverting now to the male die 10, shown particularly in FIG. 1,attention is directed to the generally conical offstanding discdeforming members 2828, previously described.

In the manufacture of the second embodiment of the nozzle, which isshown in FIG. 8, the generally conical members 28-28 are eliminated andin lieu thereof the male die member is provided with struck-uppyramidlike portions which are capable of severing through the wall ofthe disc along three lines, all of which communicate at right angles toeach other thereby providing a plurality of tangentially and angularlyoffstanding substantially equidistantly disposed coextensive tangs 36which extend sufficiently above the surface of the wall of the disc 38to thereby provide an exhaust gas outlet between the free cut area ofthe tang and the wall of the disc to cause the subsequently assembledrocket to revolve about its longitudinal axis in flight.

In FIGS. 5, 6 and 7, the final rocket assembly steps are shown. FIG.shows an exploded view of the rocket casing 50 open at one endpreparatory to insertion of the perforated propellant 52 therein. Thecasing 50 includes depressions 54 therein thus creating spaced bosses56' on the internal wall.

The view in FIG. 6 shows a relatively thin disc or wafer of aluminum 58resting on the inwardly extending rim means 56 which is created bydeforming the casing adjacent the opening, as shown. As an alternative,the wafer of aluminum, which should have a thickness not exceedingsubstantially two mils, may be secured over the offstanding nozzles andchamber and be pinched around the perimeter of the disc, whereupon thethen completed nozzle assembly may be positioned on the rim 56 or bossmeans 56 of the casing and the end portion thereof flanged over as shownat 60, in FIG. 7, to provide the completed rocket.

The primer cap 62, shown only in an exploded view 4 in FIG. 7, may beassembled into the cavity 31 of the nozzle in any convenient stage ofthe operation, whether prior to assembly of the nozzle into the casingor as a final step after complete fabrication of the rocket.

That which is claimed is:

1. A miniature rocket comprising an elongated cylindrical casingincluding a Wall, a reduced nose portion and an open end portion adaptedfor insertion of a perforated propellant into said casing, a propellantin said casing, said casing wall being provided with means providing areduced area adjacent its open end, a preformed disc-like nozzle inserthaving a perimeter lockably positioned in the open end of said casingand in edge contact with said means providing the reduced area, saidnozzle insert including an axially extending primer chamber having aprimer therein, said primer chamber also having a perforated noseportion terminating in the area of and adjacent to said propellant, athin wafer of aluminum having a distended central portion and aperipheral area is supported on the means providing the reduced area onsaid casing and interposed between the nozzle insert and said perforatedpropellant, said preformed nozzle insert further including a pluralityof substantially equidistantly disposed coextensive generally conicalruptured projections extending therefrom, each of said projections beingruptured at a common side, whereby the rocket will be caused to revolveabout its longitudinal axis in flight.

2. A miniature rocket as claimed in claim 1, wherein the peripheral areaof the wafer of aluminum is secured to the perimeter of the nozzle.

References Cited UNITED STATES PATENTS 2,412,173 12/1946 Pope.

2,605,607 8/1952 Hickman.

2,661,691 12/1953 Brandt.

2,701,525 2/1955 Hickman 10249.7 X

2,750,887 6/1956 Marcus 60201 2,762,193 9/ 1956 Johnson.

2,853,946 9/1958 Loedding 10249.3

2,938,430 5/1960 Pion l0249.7 X

2,990,684 7/1961 Cohen.

3,269,313 8/1966 Willmann et al 10249.7

VERLIN R. PENDEGRASS, Primary Examiner.

US. Cl. X.R.

